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            Track Circuit Shunting Performance Study
      

      
  Document Series
              Research Results


      
  Author
          Federal Railroad Administration


      
Report Number
              RR 21-13

  Office
              RDI-23


      Subject
                    Communications


      
  Keywords
              Track circuits, shunt, shunting


      

      
      
              
                  
      
              
  Document
              Track Circuit Shunt-A.pdf (407.66 KB)

      
              Transportation Technology Center, Inc. conducted a series of experiments between April 2012 and January 2014 to determine train characteristics and track conditions that affect shunting performance at two revenue service test locations. Optimization of track circuits for train detection is an ongoing effort by the railways and signal equipment suppliers. Most track circuits can be made more effective by having clean ballast and good track drainage. Whetting currents increase the sensitivity of track circuits to shunting and are used effectively at many locations. Use of signal averaging on island circuits has also improved shunt reliability.
      
            
      
      
              Last updated: Friday, July 30, 2021 U.S. DEPARTMENT OF TRANSPORTATION

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